Hotkeys are used to center the screen at a user-defined position or to follow specific item or units. They can help you keep track of where things are.

For example it would be smart to make a hotkey for a magma forge on level 122, while the rest of your fortress being on level 1 - 20. So you don't have to maniacally smash > (level down) to reach your forge. Other good example is to hotkey a good mining location in the caverns.

To set a hotkey to zoom to a certain location, enter the Hotkey menu at the main menu to bring up the screen. You will then see a menu with all your current hotkeys. Move your screen to the 'view' you want to hotkey to, and then press the hotkey sequence you'd like to use for the location. This will get you to the right place on the menu. Then, press z and the hotkey will be all set up! Likewise, to change the name of a hotkey while in the hotkey menu, highlight the hotkey in question, then press n, then input a name and press enter.

To set a hotkey to follow an item or a unit, go to its profile screen using u-v or v-z. From that screen, pressing any hotkey will assign it to that unit. Currently, it is only possible to assign a hotkey to units that are civilians, as attempting to "view" other types of units leads to the description screen and not the profile screen. As a workaround, you can instead assign a hotkey to an item carried by that unit, using v-i-Enter